AURORA, Ohio (AP) _ It's a good thing that ballerina Ellen Costanza only has 24 counts to get out of her penguin costume before diving into a 55-degree whale pool.

''That doesn't give you time to think about anything,'' she said Wednesday at dress rehearsal for a Cleveland Ballet benefit at Sea World of Ohio. ''And once you get in, all you think about is getting over to the side.''

Ms. Costanza and Dennis Nahat, the ballet's artistic director, both will take the plunge during Friday's performance, which is expected to raise about $40,000 for the ballet.

''I swim with my point shoes on. That's worse than the cold water,'' said Ms. Costanza, 35, who has been dancing professionally for 16 years. The native of Teaneck, N.J., began studying ballet in New York at age 9.

''I've never had a soaking wet pair of point shoes on my feet. They felt like cement boots.''

The show also marks the opening of Sea World's new, $3.2 million Penguin Encounter exhibit.

Ms. Costanza opens the show in a penguin costume, dancing to the song, ''Puttin' on the Ritz,'' sung by Judy Garland and Fred Astaire.

Nine other dancers don penguin costumes to dance on a stage above the water in Shamu Stadium before Nahat and Ms. Costanza make their aquatic exits.

Killer whales Shamu and Namu get in on the act, along with four dolphins - Cindy, Sandy, Dolly and Starbuck.

Chuck Tompkins, 28, animal behaviorist at Sea World said he worked with the animals on the show for two weeks.

''All we're doing is bringing out the animals and they're doing what comes naturally. They love performing, they love jumping.''

Nahat said the animals give him a chance to relax on stage.

''You have to remember that no one is watching the dancers when those beautiful animals are out there,'' said the founder of the Cleveland Ballet, which will mark its 10th anniversary in August.

He said he considers the performance to be dance rather than ballet.

For Ms. Costanza, the show will mark her return to the Cleveland Ballet after a year's leave of absence for injuries.

''It's really a riot,'' she said. ''Here I am with this penguin outfit on, nobody would believe this.''